The present invention relates to novel reusable relatively large shipping containers which are strong and weather resistant, for the shipping of products by a supplier to a customer, and to wall sleeves for such containing which are capable of being folded into compact size for shipment back to the supplier for reuse, and to novel brace and hinge members for use thereon.
It is desirable for reasons of economy and conservation to be able to reuse large, relatively expensive bulk shipping containers. Moreover some companies require the use of reusable containers by suppliers in order to reduce cost, and also to avoid the problems of disposing of conventional shipping containers designed for single use.
Most shipping containers are made from corrugated paper board or cardboard, which is not sufficiently strong or weather resistant to render it practical for reuse, especially in the case of large containers designed to contain heavyweight materials and requiring mechanical lifting assistance such as by use of supporting wooden pallets and fork-lifting equipment. Reference is made in U.S. Pat. No. 4,392,606 which discloses collapsible bulk containers comprising a cardboard sleeve section formed by wrapping two superposed lengths of cardboard around each other and prebanding the sleeve section with banding material, the sleeve section being capable of being folded flat and also being unfolded to squared condition for assembly with top and bottom cap members to form the container adapted to be supported on a pallet or other surface. Such bulk containers are not made for reuse, do not have integral hinge members or brace members and thus require bulge-resistant peripheral strapping, and do not have end walls which are foldable inwardly between the side walls to a compact size which fits within the cap members to provide a collapsed container which requires a minimum of space for storage or shipping.
Some shipping containers are made from wood, which may be durable and weather resistant. However such containers are bulky and heavy, so as to be expensive to ship back to the supplier. Also, wooden containers generally are nailed together and therefore may be difficult to open without damaging the wood and destroying the reusability of the container. Also, wood is relatively brittle and susceptible to cracking during shipment, lifting, discharge of contents, etc.
It is known to use rigid metal and plastic shipping containers which avoid many of the difficulties inherent in the use of other construction materials such as cardboard and wood. The main problem with such shipping containers is their bulk, which presents an expense and a storage problem for both the customer and the supplier. Empty rigid shipping containers require as much room as filled containers during storage and also during shipping.